Lewis & Short

ornātĭo, ōnis, f. [orno], an adorning, adornment, ornament (not ante-Aug., and very rare), Vitr. 5, 8, 8: ornationes templi, Inscr. Orell. 775: STATVAE, Inscr. ap. Nov. Lett. di Firenze, t. ii. p. 600.